Compressor arrangements are well known from the prior art. DE 197 18 455 A1, for example, describes a compressor arrangement wherein the ground coffee from a grinder is compressed according to specifications regarding filling weight and filling volume. The ground coffee to be filled must thereby have a defined bulk density (gram per cm3). For this purpose, the compressor arrangement of DE 197 18 455 A1 has a retention flap at an outlet opening of the compressor arrangement which can be adjusted with an opening angle from 0° to 90° depending on the desired bulk density. A measuring means for the bulk density or the degree of compaction is provided in the region of the outlet opening so that a regulation is possible via an adjustment of the retention flap.
The above-described arrangement of the measuring device in the region of the outlet opening is complicated and is therefore costly and susceptible to failure. Sudden variations in the quantity of ground coffee in the compressor which are caused, for example, by ground coffee slipping from side walls of the compressor trough, cannot be further compensated for so that overload damage to the first drive device may result.